Coralville Lake is the recreation hub of the Iowa City area – a 5,000-acre reservoir on the Iowa River that’s as famous for its geology as its fishing. When record floods sent water roaring over its emergency spillway, they scoured away the soil to reveal a 375-million-year-old Devonian fossil seabed, now the remarkable Devonian Fossil Gorge. Add great fishing, boating and trails, and it’s one of eastern Iowa’s best lakes.
This guide covers Coralville Lake: the fishing, the Devonian Fossil Gorge, the recreation, and access. It’s part of our growing Iowa Lakes Database.
Coralville Lake at a glance
- Surface area: ~5,000 acres on the Iowa River
- Location: Johnson County, eastern Iowa (near Iowa City & Coralville)
- Built: Coralville Dam, completed 1958 (U.S. Army Corps of Engineers)
- Top fish: walleye, white bass, crappie, channel catfish, bluegill, largemouth bass
The Devonian Fossil Gorge
Coralville’s most extraordinary feature was uncovered by disaster. During the great floods of 1993 (and again in 2008), water poured over the dam’s emergency spillway and stripped away soil and rock, exposing a 375-million-year-old Devonian seabed packed with the fossils of ancient corals, crinoids and sea creatures. Today the Devonian Fossil Gorge is a free, walkable outdoor museum below the dam – a chance to walk across a fossilized tropical sea floor, one of the most unusual attractions on any Iowa lake.
Fishing Coralville Lake
The reservoir is a solid eastern-Iowa fishery: walleye, white bass, crappie, channel catfish, bluegill and largemouth bass. An Iowa fishing license is required. The tailwater below the dam is popular, and the lake’s coves and the river above hold fish through the season. As a flood-control lake, the level fluctuates.
Recreation, trails and Lake Macbride
The Corps provides campgrounds, beaches, marinas and boat ramps around the lake, with boating, sailing, swimming and fishing all popular – and the proximity to the University of Iowa keeps it lively. Trails connect parts of the shoreline, and the lake adjoins Lake Macbride and its state park, giving the area two connected lakes to explore.
Getting there and what’s nearby
Coralville Lake is just north of Coralville and Iowa City in eastern Iowa, off I-80, about 30 minutes from Cedar Rapids. The University of Iowa, the Amana Colonies and Lake Macbride State Park are all nearby.
Know before you go
- Fishing license: an Iowa license is required.
- Visit the gorge: the Devonian Fossil Gorge below the dam is free and fascinating.
- Fluctuating level: a flood-control reservoir – check conditions before launching.
Frequently asked questions
What is the Devonian Fossil Gorge?
A 375-million-year-old fossil seabed below Coralville Dam, uncovered when floods scoured the spillway in 1993 and 2008 – now a free, walkable outdoor museum of ancient sea life.
What fish are in Coralville Lake?
Walleye, white bass, crappie, channel catfish, bluegill and largemouth bass.
Where is Coralville Lake?
Just north of Coralville and Iowa City in Johnson County, eastern Iowa, off I-80.
Related: explore more of the largest lakes in Iowa, or head back to the Iowa Lakes Database.
